Diaphragm pump



L. F. WILSON DIAPHRAGM PUMP Get. 19, 1954 4 Sheets-Sheet 1 Filed Aug.23, 1950 INVENTOR.

LAWRENGE E WILSON HIS ATTORNEY L. F. WILSON DIAPHRAGM PUMP Oct. 19, 19544 Sheets-Sheet 2 Filed Aug. 23, 1950 mil 1 M H n r .iu mag x Z2 #:IW-WJ- 7 0- FIG-3 INVENTOR. LAWRENCE E WILSON ms arro'awsr Oct. 19, 1954 wso 2,691,943

DIAPHRAGM PUMP Filed Aug. 23, 1950 4 Sheets-Sheet 3 I l M 5 74 174 \H1mm @5 5, m E m 83 a3 82 82 6+! F765 F166 INVENTOR.

LAWRENCE E WILSON HIS A TT ORA/E Y L. F. WILSON DIAPHRAGM PUMP Oct. 19,1954 4 Sheets-Sheet 4 Filed Aug. 25, 1950 IN VENTOR. LAWRENGE E WILSONHIS ATTORNEY Patented Oct. 19, 1954 UNITED STATES ATENT OFFICE DIAPHRAGMPUMP Application August 23, 1950, Serial N 0. 181,018

12 Claims. 1

This invention relates to pumps, and more particularly to pumps designedto measure a predetermined volume of liquid during each stroke or cycleof the pump.

This invention is particularly adapted for use with corrosive fluids orthose containing gritty particles, tending to corrode or cut out theinterior walls of the working parts of an ordinary pump, as well as withfluids which would become contaminated if allowed to contact theinterior surfaces of an ordinary pump.

One object of the invention is to provide an improved pump having a morepractical and eflicient type of construction, for accurately measuringand pumping a predetermined volume of fluid during each stroke or cycleof the pump.

Another object is to provide a pump of the above character which hasmeans for precisely adjusting and regulating the volume of fluidmeasured and pumped.

Another object of the invention is to provide a pump having the aboveadvantages and which is particularly adapted for use with corrosivefluids, fluids containing gritty particles or fluids which would becontaminated if allowed to contact the interior surfaces of an ordinarypump.

Another object of the invention is to provide a pump of the abovecharacter haying a minimum clearance volume, the proportions of whichremain constant regardless of the length of the pumping stroke therebyinsuring a uniform volume of fluid pumped per stroke and providing animproved pump construction adapted for pumping liquified gases which, atgiven operating temperatures, may be supplied at pressures closer totheir vapor pressures than was heretofore possible.

A further object of the invention is to provide a pump having the aboveadvantages and which is compact in size, flexible in operation andcapable of producing a. high pressure in the fluid to be pumped.

Still a further object of the invention is to provide a pump having theabove advantages in a more practical and eflicient type of constructioncapable of being readily manufactured and of operating in an accurateand reliable manner.

To these and other ends the invention resides in certain improvementsand combinations of parts, all as will be hereafter more fullydescribed, the novel features being pointed out in the claims at the endof the specification.

In the drawings:

Fig. l is an elevation view of a pumping and measuring mechanismembodying the present invention showing the location of, and theconnections between, the measuring pump, the adjustable regulating valvemechanism and the motor driven actuator;

Fig. 2 is a fragmentary top plan view of the pumping and measuringmechanism, as shown in Fig. 1;

Fig. 3 is an elevation view, partly in section, of the actuator showingthe construction of the hollow piston and movable cylinder;

Fig. 4 is a side elevation view of the actuator as shown in Fig. 3showing the means for connecting the cylinder to a motor driveneccentric;

Fig. 5 is an enlarged elevation View of the measuring pump and certainof its connecting means;

Fig. 6 is a sectional elevation substantially on line 6-6 in Fig. 5showing the internal construction of the measuring head and the locationof the flexible separating diaphragm;

Fig. 7 is an enlarged sectional elevation taken through the center ofthe adjustable regulating means parallel with the longitudinal axisthereof and showing the free piston in position for uncovering thebypass port, and

Fig. 8 is a sectional view substantially on the line 8-8 of Fig. 7showing the location of the bypass port.

The preferred form of the invention, herein disclosed by way ofillustration, comprises a motor driven actuator or pump ll (Fig. I) forproducing an actuating fluid flow alternately in opposite directions, ameasuring pump [2 adapted to be actuated by said first fluid for pumpinga second fluid in measured quantities and an adjustable regulating means[3 interposed between and connected to said actuator and said measuringpump by connecting pipes M and I 5, respectively (Fig. 1). c,

The actuator or pump H comprises, preferably, an elongated piston I6(Figs. 3 and 4) mounted for rocking movement and received in a cylinderI? having a rocking and reciprocating movement for pumping cooperationwith the piston. The piston is fixed to and extends upwardly from theupper end of a rocking yoke I8 having depending arms [9 provided withopenings seated on the ends of a short shaft 20 mounted to rock in aself-aligning bearing 2|- (Fig. i). A set screw 22 serves to fix theyoke to the shaft. To provide the piston with efficient packing orsealing means, its upper end is reduced as at M (Fig. 3) to form ashoulder 25. The reduced portion 24- carries two packing rings in theform of cup-shaped gaskets, 26 and 21, preferably of leather or othersuitable material, and cupped upwardly toward the free or pressure sideof the cylinder, to provide an efficient sealing fit in the cylinderwith low frictional resistance, as well understood in the art. Ring 2'!is spaced upwardly along piston Hi from ring 25 by a metallic cupfollower 28. A second cup follower 29 is inserted between upper ring 21and the end of the piston I5. Nut 3|, threadedly secured to the upperend of piston I6, engages the upper surface of cup follower 29 and holdsthe above sealing rings and cup followers firmly in place as shown inFig. 3.

Piston l has a hollow passageway 32 (Fig. 3) extending longitudinallyfrom the upper or free end thereof into the upper portion of pistonyo-ke H; where said passageway is intersected by a transverselyextending hollow passageway 33 (Figs. 3 and 4) which extends inwardlyfrom outer face 34 of piston yoke l8. Passageways 32 and 33 thus form acontinuous path through which fluid is forced when the cylinder isreciprocated by means hereafter described. The outer portion ofpassageway 33 is threaded for connection to said conduit l4.

When cylinder I1 is in its lowermost position as shown in Figs. 3 and 4,the upper end 35 (Fig. 3) of bore 23 of the cylinder is slightly abovethe upper end 36 of piston l5 and thereby provides a small clearancevolume which is intersected by two transversely extending bores 3i and3B which are adapted to be connected to a vacuum relief inlet valve 39and a pressure relief valve 4 respectively, the functions and operationof which will be hereafter more fully explained.

The upper end of cylinder I7 is fixed to the lower end of a connectingrod 42 by a bolt 43 (Figs. 3 and 4). Connecting rod 42 has its upper oropposite end formed with a bearing 44 receiving a short shaft Ortrunnion 45 which is eccentrically mounted on an eccentric disk 46 (Fig.4). Connecting rod 42 is held in place on trunnion 45 by a bolt 41 andwasher 48. Disk 45 is fixed, as by a key 49 on the shaft 56 of anelectric motor 5| (Fig. l) which supplies the power for rotating saideccentric disk and thereby operating the actuating pump.

The actuating pump H is adapted to be secured either to a support 53(Fig. 1) located within a tank 54 containing the oil or other actuatingfluid, or directly to the bottom 55 of the tank and is connected byconduit I4, to an adjustable regulating valve which will hereafter hedescribed.

It is intended that the upper surface of the actuating or pumping fluidextend above inlet valve 39 and release valve 4|, as shown at 55 (Fig. lto minimize the possibility of air being drawn into the system and, toinsure an ample supply of fluid under all adjustments, the actuatorpumps a greater volume of fluid per stroke than is required for theoperation of the regulating valve H) and measuring pump I2. The excessfluid is allowed to escape through pressure relief valve 4| into tank54. A second pressure relief valve 6!! (Fig. 1) having a return conduitill emptying into tank 54, is inserted between regulating valve I3 andmeasuring pump l2, as hereafter more fully described.

Thus, it will be seen that when electric power is supplied to motor 5|,eccentric disk 46 is rotated and cylinder I1 is caused to reciprocatealong piston l6. As the cylinder moves upwardly from its lowermostposition as shown in Fig. 3, reduced pressure is formed in the cylinderwhich draws fluid from the regulating valve i3 through conduit i4 andchambers 33 and 32. As the above volume of fluid is not sufficient torelieve the reduced pressure within said cylinder, atmospheric pressureon fluid in the tank operates the normally closed, spring actuated,vacuum relief inlet valve 39, which opens and allows the fluid to flowinto the cylinder and keep it filled. As the cylinder reverses directionand moves downwardly to the position as shown in Fig. 3, valve 39 closesand the fluid is forced downwardly and outwardly through passageways 32and 33 and through conduit l4 into regulating valve I3. Thus during eachstroke or cycle of the actuating pump, the fluid in conduit I4 is movedalternately in opposite directions under suband super-atmosphericpressure, respectively.

The actuating fluid, under the pulsating pressure described above,passes through regulating valve l3, by means which will be hereafterdescribed and is carried by conduit l5 to measuring pump I2 foractuating the same.

Measuring pump |2 comprises a pair of cylindrical plates 51 and 58, ofcorrosion resisting material, as for example, stainless steel and havinga substantial thickness as shown in Fig. 6 and thus are adapted towithstand high fluid pressures. Plates 5? and 58 are formed withtransversely extending bores 59 and 5|, respectively. Bore 59 is closedat one end by a plug 52 and has attached to its opposite end a nipple 63which is adapted to receive conduit |5 for transmitting the actuatingfluid into said chamber. Plate 51 has formed therein a series of holes54 (Figs. 5 and 6) which extend transversely to the longitudinal axis ofbore 59 and connect it with the interface 55 of the plate. Plate 58 hasa similarly formed series of holes 55 which connect its interface 51with bore 6|. Plates 5i and 58 are adapted to be securely fastenedtogether by studs 68 and nuts 69 with interfaces 65 and 6?,respectively, substantially in contact with one another, as shown inFig. 6.

A thin flexible diaphragm ll preferably of stainless steel, rubber or aninert plastic, is securely fastened between interfaces 65 and 61 andthus forms a liquid-proof seal between bores 59 and 6| and their seriesof holes 54 and 55. Interfaces 65 and 51 are concavely recessed inwardlyadjacent the center portions thereof as at T2 and 13, respectively, andthus provide a space divided into two separate chambers by the movablewall or flexible diaphragm TI. This partitioning diaphragm is adapted tobe moved in response to the pulsation of the actuating fluid passingthrough bore 59 and holes 54, into the space between the diaphragm andthe recessed interface of plate 5?, such movement of the diaphragmserving to alternately enlarge and contract the chamber between theopposite side of the diaphragm and the interface of plate 58 to effectpumping of a second fluid to be measured as hereafter more fullydescribed.

Plate 58 has connected therewith adjacent each end of bore 5| a doubleball check valve assembly, indicated generally by the numerals 74 and15, respectively, for insuring unidirectional flow of fluid through saidchamber in response to the movement of the diaphragm 1|. As these valveassemblies are of similar construction a description of one will besuflicient. Thus, the lower or inlet valve assembly 15 (Fig.

6) comprises a collar 16 attached to plate 58. A

pair of cup-shaped valve blocks 11 and 18 and ball valves 19 and 8| areinserted within collar 16. A flanged nipple 82 abutting the outermostvalve block is securely held in place by a nut 83 screwed into the outerend of collar 16. Valve blocks 11 and 18 are formed with valve seatshaving sharp edges which insure proper closing of the ball valves. Adrain cock 84 is attached to collar 76, as shown in Fig. 6, to allowremoval of any fluid which may leak out around the valve assembly withincollar 16.

The lower valve assembly is adapted to allow fluid to move into chamber6| but to prevent the fluid from moving out of the chamber through thevalve assembly. The upper or outlet valve assembly M is similar to theinlet valve assembly but is arranged to allow fluid to pass from chamber6| out through valve assembly M and to prevent fluid from moving throughthe valve assembly into said chamber. Thus, it will be seen that whennipple 82 leading from the inlet valve assembly is attached to a fluidsupply, the reciprocating movement of flexible diaphragm alternatelycreates a superand sub-atmospheric pressure region in bore 6| andalternately draws fluid into said bore through inlet valve assembly T5and discharges the fluid through the outlet valve assembly 14.

The movement of diaphragm H to the right is restricted by recessedportion 73 of interface 61 and to the left by recessed portion 12 ofinterface 65. Each time the diaphragm moves from a position in contactwith recessed portion 73 to a position in contact with recessed portion12, and back again to its initial position, it has displaced a. constantvolume. Thus, as the diaphragm is caused to reciprocate in response tothe pulsations or pressure changes in the actuating fluid, pump l2measures a constant volume of fluid for each cycle of movement of theflexible diaphragm.

My invention also comprises a novel regulating means l3, interposedbetween actuator II and measuring pump l2, for accurately regulating andcontrolling, per cycle, the volume of a second fluid measured by pumpi2. This regulating means, as presently more fully described, restrictsthe movement of diaphragm H to the left,'as seen in Fig. 6, and therebylimits the volume per cycle of fluid drawn into bore 6| and itsconnected diaphragm chamber.

Regulating means I3 comprises basically a cylinder, shown generally at85 (Fig. 7), and a closely fitting free piston 86 which is adapted tomove in opposite directions. in response to the pulsations of theactuating fluid. Cylinder 85 comprises a body section 81 (Fig. 7) whichhas grooves at opposite ends thereof containing split rings 88 andflanges 89 for connecting said body portion to end members 9| and 92,respectively. Said flanges are fastened to said end members by bolts 93.A gasket 94 located at each end of cylinder body section 8'! insures atight seal between said body section and end members 9| and 32. Endmember 9| has a threaded opening 95 adapted to be connected to conduitHI for transmitting the: actuating fluid to and from said cylinder. Endmember 92 has a bore 96 extending from its. inner surface partiallytherethrough and forming at the outer end thereof a shoulder 97. Asmaller counterbore 98 connects said bore 95 with a threaded opening 9-9which is adapted to be connected to conduit I5. Bore 96 is slightlysmaller in diameter than the bore of cylinder 8i and thus forms a stopfor restricting the movement in one direction of piston 86. A bore 0|extends inwardly from the right hand end of piston 86, as seen in Fig.7, partially through said piston. A coil compression spring I92 isinserted in bore [0| and has one end thereof in contact with the innerend of said bore and the opposite end thereof in contact with shoulder91 for moving the piston to the left as viewed in Fi 7.

Body portion 87 is provided with a bypass port I93 (Figs. 7 and 8)adjacent the right hand end thereof as viewed in Fig. 7, which allowsmakeup actuating fluid to flow from cylinder 8'! around the piston andout through outlet 99 and conduit I5 to the measuring pump bore 59, tokeep its passageways filled. However, bypass port I63 is of limitedextent so that it is open only when piston is adjacent its right handposition as shown in Fig. 7.

Thus, as the actuating fluid enters cylinder 81 under super-atmosphericpressure it causes piston 85 to move to the right, as seen in Fig. 7,thereby forcing the actuating fluid to flow through outlet 99 andconduit id to the measuring pump where it moves diaphragm ii to theright as viewed in Fig. 6.

If at any point during this downward stroke of actuator cylinder H thepressure of the actuating fluid exceeds a predetermined amount, reliefvalve Gil opens to relieve said excessive pressure and allows the excessfluid to return to tank 54 by return conduit 10.

Valve 5t not only relieves the actuating system of the excess fluid perstroke, as pointed out above, but as it is located at the highest pointin the actuating fluid system, as for example, between nipple '63 andconduit i 5, it also bleeds any air or gas bubbles entrapped in theactuating fluid. It has been found desirable when pumping a second fluidat a given pressure to set the actuating fluid pressure relief valves 68and 4| to open at pressures slightly greater than the above givenpressures. In normal operation, therefore, when pumping the second fluidat a given pressure, as for example, 1009 p. s. i., the actuating fluidmoves diaphragm into contact with recessed portion it after which thepressure of the actuating fluid continues to build up until it reaches apredetermined amount, as for example, 1100 p. s. i., at which pointvalve 68 opens. Thus, once every cycle, valve 86 opens to allow a smallamount of actuating fluid and entrapped gas bubbles to escape. If valve99 fails to operate, or for any reason the pressure in the actuatorexceeds a second predetermined amount, as for example, 1200 p. s. i.,relief valve 4| opens allowing the excess fluid to escape into container54 thereby protecting the actuating fluid system.

When actuator cylinder ll moves upwardly, creating a region ofsub-atmospheric pressure in said actuator, the actuating fluid is drawnout of cylinder 81 thereby drawing piston 5'5 to the left, assistedinitially by spring Hi2. More specifically, this movement of piston 86quickly closes bypass port its and shuts off the flow of the actuatingfluid therethrough. However, as piston 86 moves to the left, it createsin bores 9t and 98 a reduced pressure which withdraws the actuatingfluid from measuring pump bore 59 and its connected diaphragm chambers.The farther piston 85 moves to the left, as viewed in Fig. 7, thegreater the reduction in pressure and the greater the amount of fluiddrawn out of bore 59. This increases the distance through whichdiaphragm H is moved away from recessed portion I3 towards the oppositerecessed portion I2 and simultaneously increases the volume of fluiddrawn in through bore 6| during the movement of said diaphragm. It isevident that if piston 86 is allowed to travel through a sufficientdistance, diaphragm II will contact recessed portion I2 thereby drawingthe maximum volume of fluid into bore 6| and its connected diaphragmchambers. Conversely, if the leftward movement of piston 86 isdecreased, the amount of actuating fluid drawn out of bore 59 will beless and diaphragm II will move through a correspondingly smallerdistance thereby drawing a smaller amount of fluid into measuring bore6I.

As actuator cylinder II moves downwardly the actuating fluid is againunder super-atmospheric pressure and piston 86 moves to the right to theposition as shown in Fig. '7, thereby forcing fluid into chamber 59 andmoving diaphragm II in the opposite direction until it strikes againstrecessed portion I3. Thus, limiting the leftward movement of piston 86,as viewed in Fig. 7, restricts the movement of flexible diaphragm IItowards recessed portion I2 and volume of fluid per cycle drawn into andpumped out of bore 6 I.

The means for restricting the movement of piston 86 comprises a variablyadjustable stop rod I04 (Fig. 7) which passes longitudinally through anextension I05 of end member 9!. A manually rotatable cap I06, bored atthe outer end thereof to allow the outer end of rod I04 to extendtherethrough, is threadedly engaged with extension I05. A pin or setscrew II secures said rod to said cap, so that as cap I06 is rotated toscrew it on extension I05, rod I04 is moved longitudinally through saidextension and into cylinder 81. A collar I08 is secured by set screw I09to rod I04 inside the cylinder and provides a means for limiting theoutward movement of rod I04 as shown in Fig. 7. By rotating cap I06 asdescribed, rod I04 is moved inwardly as far as desired towards the rightend Of cylinder 8! to arrest and limit the leftward movement of piston86, for the purposes pointed out above. Extension I-has adjacent theouter end thereof two packing rings I I I to prevent leakage ofactuatingfluid along rod I04. A nut H2 is securely fastened to theoutermost end of rod I04 as shown in Fig. 7 and provides a means for theattachment of a wrench or other suitable tool.

It will be seen that when the actuating fluid is under super-atmosphericpressure, piston 86 is moved into contact with end portion 92 and theactuating fluid passes into the measuring pump, thereby moving diaphragmII to the right until stopped by recessed portion I3. As the actuatingfluid is thereafter subjected to sub-atmospheric pressure, piston 80 isdrawn to the left until it engages stop rod I04. As pointed out above,the greater the leftward movement of piston 86, the greater is theleftward movement of diaphragm II and the greater is the volume of fluiddrawn into the measuring pump. When the actuating fluid is again undersuperatmospheric pressure, the above cycle is repeated causing diaphragmII to move again to the right to expel through outlet valve M the fluidwhich was previously drawn into measuring bore 6I through inlet valve15.

It is apparent from the above description that the invention supplies apositive displacement diaphragm pump for accurately metering and pumpingliquids under pressure. The spring tenthus reduces the v sion at whichthe automatic relief intake and discharge valves 39 and .60 operate isso determined as to insure the full desired operating stroke of theregulating piston 86 before the valves operate to relieve the actuatingpump I I. That is, on the upward or suction stroke of cylinder H, thereduced pressure moves piston 86 to the left in Fig. '7 until arrestedby stop means, such as the end of the rod I04, after which the reliefinlet valve 39 opens to supply additional oil from the reservoir to thepump I I, depending in quantity on the length of stroke of piston 86 ascontrolled by stop rod I04. This suction stroke first withdraws the oilor other actuating fluid from the left hand side of the diaphragm (Fig.6) to move the 'diaphragm toward the left to a distance controlled bythe setting of the stop rod I04 and thus, movement of the diaphragmdraws fluid to be pumped past the lower check valves, I9 and 8|, to flllthe chamber and connections at the other side of the diaphragm.

During the downward or pressure stroke of cylinder H, the oil pressureforces piston 86 toward the right (Fig. 7) thereby forcing the liquid atthe other end of the piston back into the diaphragm chamber, to forcethe diaphragm against the concave face I3 of plate 58. This forces thefluid to be pumped under positive pressure from this daphragm chamberthrough bore BI and the upper or outlet check valves. During this strokeof piston 86, it compresses spring I02 and uncovers port I03 to insure afull supply of the actuating fluid to the diaphragm chamber and fullpressure on the diaphragm to complete its pumping pressure stroke, afterwhich relief discharge valve 60 opens to permit excess oil to flow fromthe actuating fluid system into the reservoir. If for any reason valve60 fails to operate or fails to reduce the pressure of the actuatingfluid, a second pressure relief valve 4I opens, thereby permitting theactuating fluid to escape from cylinder Il into container 54.

On the subsequent suction stroke, spring I02 quickly initiates andassists the return movement of piston 86. Such movements of regulatingpiston 86 in opposite directions cause the pumping diaphragm II to movein direct volumetric relation and since the diaphragm, at the end of thepressure stroke, is hydraulically forced to conform to the machinedconcavity of plate 58, the liquid volume held between the inlet andoutlet check valves of the metering pump, hereafter referred to as theclearance volume, is a minimum volume and remains constant regardless ofthe length of stroke of the pump. Stop ro'd I04 may be preciselyadjusted for controlling said stroke length by screwing the'cap I06 onthe extension I05, thus providing an adjustment of substantiallymicrometrie fineness and precision.

The above construction in which the clearance volume is always the sameand is determined solely by the engagement of diaphragm II with recessedconcavity I3, insures greater accuracy and uniformity of fluid pumpedper cycle because the compressibility of the actuating fluid does notaffect the position of the diaphragm at the end of the discharge stroke.Thus, the accuracy of the above pump does not depend on the ofteninexact balancing of hydraulic pressures on opposite sides of thepumping diaphragm as was commonly the case in the prior constructions.

Maintaining the clearance volume at minimum constant proportions meansthat regardless of the length of the pumping stroke, my improved pumphas a higher compression ratio (1. e., a

higher ratio between the total volume and the clearance volume) thanmost pumps of similar construction. A further advantage of thisconstruction is that my pump will operate satisfactorily with liquefiedgases which may be supplied at pressures closer to their vaporpressures, for their corresponding operating temperatures, than washeretofore possible with pumps of this type.

It will thus be seen that the invention accomplishes its objects andwhile it has been herein disclosed by referenc to the details of apreferred embodiment, it is to be understood that such disclosure isintended in an illustrative, rather than a limiting sense, as it iscontemplated that various modifications in the construction andarrangement or the parts will readily occur to those skilled in the art,within the spirit of the invention and the scope of the appended claims.

I claim:

1. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump having awall portion movable alternately in opposite directions by saidactuating fluid for pumping said second fluid, and a variably adjustableregulating means connected between said actuator and said measuring pumpin series hydraulically therewith for regulating the flow of saidactuating fluid from said measuring pump for restricting the movement ofsaid wall portion in one direction for controlling the amount of saidsecond fluid pumped by said measuring pump.

2. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump having awall portion movable alternately in opposite directions by saidactuating fluid for pumping said second fluid, and a variably adjustableregulat ing means connected between said actuator and said measuringpump in series hydraulically therewith, said regulating means comprisinga cylinder and piston. therein movable in opposite directions by saidactuating fluid during each cycle of said measuring pump for regulatingthe application of said actuating fluid to said measuring pump forinsuring actuation of said wall to the limit of movement thereof in thedirection for pumping second fluid and maintaining a uniform clearancevolume in the side of the measuring pump through which said second fluidis being pumped regardless of the volume of said second fluid beingpumped.

3. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, saic measuring pump having awall portion movable alternately in opposite directions by saidactuating fluid for pumping said second fluid, and a variably adjustableregulating means connected between said actuator and said measuring pumpin series hydraulically therewith, said regulating means comprising acylinder containing a piston movable in opposite directions by saidactuating fluid during each cycle of said measuring pump for controllingthe application of said actuating fluid to said measuring pump, andadjustable stop means on said cylinder for limiting the movement of thepiston in one direction for controlling the flow of said actuating fluidfrom said measuring pump for regulating the volume of said second fluidpumped by said measuring pump.

4. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump havingspaced immovable wall portions and a wall portion therebetween movablealternately in opposite directions by said actuating fluid for pumpingsaid second fluid, and a variably adjustable regulating means connectedbetween said actuator and said measuring pump in series hydraulicallytherewith, said regulating means comprising a cylinder containing apiston movable in one direction. for allowing application of the fullpres sure of said actuating fluid to one side of said movable wallportion fo insuring actuation of said movable wall portion against oneof said fixed wall portions in the direction for pumping said secondfluid vfor maintaining a uniform clearance volume in the sid of the masuring pump through which said second fluid is pumped at the end of thepumping stroke of said measuring pump, regardless of the volume of saidsecond fluid being pumped, adjustable stop means on said cylinderengaging said piston for limiting the movement thereof in the oppositedirection for controlling the flow of said actuating fluid from saidmeasuring pump for regulating the volume of said second fluid pumped bysaid movaole wall portion.

5. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump havingspaced immovable wall portions and a wall portion therebetween movablealternately in opposite directions into contact with said immovable wallportions by said actuating fluid for pumping said second fluid, avariably adjustable regulating means connected between said actuator andsaid measurirn pump in series hydraulically therewith, said regulatingmeans comprising a cylinder containing a piston movable in oppositedirections for regulating the application of said actuating fluid tosaid measuring pump, a bypass port, means for opening said port at theend of the movement of said piston in one direction for allowingapplication of the full pressure of said actuating fluid to one side ofsaid movable wall portion for insuring actuation of said movable wallportion against one of said fixed wall. portions in the direction forpumping said second fluid for maintaining a uniform clearance volume onthe opposite side of said movable wall portion at the end of the pumpingstroke of said measuring pump regardless of the volume of said secondfluid being pumped, and adjustable stop means on said cylinder engagingsaid piston for limiting the movement thereof in the OPD Site directionfor restricting the flow of said actuating fluid from said measuringpump for controlling the actuation of said wall portion in a directionopposite to said pumping direction for limiting the volume of saidsecond fluid pumped by said movable wall portion.

6. Conducting means for containing a fluid, an

actuating fluid therein, an actuator for pumping said fluid alternatelyin opposite directions, a fluid measuring pump operated by saidactuating fluid for pumping a predetermined volume of a second fluid,said measuring pump having spaced immovable wall portions and a wallportion therebetween movable alternately in opposite directions intocontact with said immovable wall portions by said actuating fluid forpumping said second fluid, a variably adjustable regulating meansconnected between said actuator and said measuring pump in serieshydraulically therewith, said regulating means comprising a cylindercontaining a piston movable in opposite directions for regulating theapplication of said actuating fluid to said measuring pump, a by-passport in said cylinder adjacent one end thereof and arranged to be openedby said piston at the end of its movement in one direction for allowingapplication of the full pressure of said actuating fluid to one side ofsaid movable wall portion for insuring actuation of said movable wallportion against one of said fixed wall portions in the direction forpumping said second fluid and maintaining a uniform clearance volume onthe opposite side of said movable wall portion at the end of the pumpingstroke of said measuring pump regardless of the volume of said secondfluid being pumped, adjustable stop means on said cylinder engaging saidpiston for limiting the movement thereof in the opposite direction forrestricting the flow of said actuating fluid from said measuring pumpfor controlling the actuation of said wall portion in a directionopposite to said pumping direction for limiting the volume of saidsecond fluid drawn into and subsequently pumped by said movable wallportion, and spring means in said cylinder urging said piston againstsaid stop means.

'7. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump havingspaced immovable wall portions and a wall portion therebetween movablealternately in opposite directions into contact with said immovable wallportions by said actuating fluid for pumping said second fluid, avariably adjustable regulating means connected between said actuator andsaid measuring pump in series hydraulically therewith, said regulatingmeans comprising a cylinder containing a piston movable in oppositedirections for regulating the application of said actuating fluid tosaid measuring pump, a by-pass port in said cylinder comprising alongitudinally-extending groove therein adjacent one end thereof, saidgroove being longer than said piston and positioned to be uncovered bysaid piston at the end of its movement in one direction for allowingapplication of the full pressure of the actuating fluid to flow throughsaid port and around said piston against one side of said movable wallportion for insuring actuation of said movable wall portion against oneof said fixed wall portions in the direction for pumping said secondfluid and maintaining a uniform clearance volume on the opposite side ofsaid movable wall portion at the end of the pumping stroke of saidmeasuring pump regardless of the volume of said second fluid beingpumped, adjustable stop means on said cylinder engaging said piston forlimiting the movement thereof in the opposite direction for restrictingthe flow of said actuating fluid from 12 said measuring pump forcontrolling the actuation of said wall portion in a direction oppositeto said pumping direction for limiting the volume of said second fluiddrawn into and subsequently pumped by said movable wall portion, andspring means in said cylinder urging said piston against said stopmeans.

8. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump comprisingspaced immovable wall portions having therebetween a movable wallportion forming two chambers in said pump, said movable wall portionbeing movable alternately in opposite directions by the pressure of saidactuating fluid in one of said chambers for pumping said second fluidthrough the other of said chambers, and a variably adjustable regulatingmeans connected between said actuator and with one of said chambers inseries hydraulically therewith for regulating the application of saidactuating fluid from said chamber for controlling the volume of saidsecond fluid drawn into and, subsequently pumped by the other of saidchambers.

9. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump comprisingspaced immovable wall portions having therebetween a movable wallportion forming two chambers in said pump, said movable wall portionbeing movable alternately in opposite directions by the pressure of saidactuating fluid in one of said chambers for pumping said second fluid,and a variably adjustable regulating means connected between saidactuator and said one of said chambers in series hydraulically therewithfor regulating the flow of said actuating fluid from said chamber forrestricting the movement of said flexible diaphragm in one direction forcontrolling the volume of said second fluid drawn into and subsequentlypumped by the other of said chambers.

10. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump comprisingspaced immovable wall portions having therebetween a movable wallportion forming two chambers in said pump, said movable wall portionbeing movable alternately in opposite directions by said actuating fluidfor pumping said second fluid, conducting means connected with one ofsaid chambers and provided with automatic valve means for maintainingunidirectional flow of said second fluid through said chamber, and avariably adjustable regulating means connected between said actuator andthe other of said chambers in series hydraulically therewith forregulating the flow of said actuating fluid from said chamber forrestricting the movement of said flexible diaphragm in one direction forcontrolling the volume of said second fluid drawn into and pumped by thefirst mentioned chamber.

11. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping asecond fluid, a variably adjustable regulating means connected betweensaid measuring pump and said actuator in series hydraulically therewithfor regulating the application of said actuating fluid to said measuringpump alternately in opposite directions for actuating said pump tosupply said second fluid at a predetermined rate, and pressure reliefmeans operated by said actuating fluid for limiting the maximum pressureexerted by said fluid and for bleeding entrapped gas bubbles from saidfluid.

12. Conducting means for containing a fluid, an actuating fluid therein,an actuator for pumping said fluid alternately in opposite directions, afluid measuring pump operated by said actuating fluid for pumping apredetermined volume of a second fluid, said measuring pump having awall portion movable alternately in opposite directions by saidactuating fluid for pumping said second fluid, a variably adjustableregulating means connected between said actuator and said measuring pumpin series hydraulically therewith for regulating the flow of saidactuating fluid from said measuring pump for restricting the movement ofsaid wall portion in one direction for controlling the volume of saidsecond fluid pumped by said measuring pump, and pressure relief meansoperated by said actuating fluid for limiting the maximum pressureexerted by said fluid and for bleeding entrapped gas bubbles from saidfluid.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,046,491 Scott July 7, 1936 2,260,306 Ferguson Oct. 28, 19412,303,597 Adelson Dec. 1, 1942 2,345,693 Wilson Apr. 4, 1944 2,361,460Daugherty Oct. 31, 1944 2,413,851 Taylor Jan. 7, 1947 2,608,933 FerrisSept. 2, 1952

